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A factory worker pushes hard against a heavy toolbox to keep it at rest on a ramp. Is he doing work?

Short Answer

Expert verified
No, the worker is not doing work because there is no displacement.

Step by step solution

01

Define the concept of work

In physics, work is done when a force causes displacement of an object, and it is calculated as the product of the force and the displacement in the direction of the force. The formula for work is given by \( W = F \cdot d \cdot \cos(\theta) \), where \( W \) is work, \( F \) is the force applied, \( d \) is the displacement, and \( \theta \) is the angle between the force and displacement.
02

Analyze the scenario

In the given scenario, the factory worker is pushing against the toolbox, which remains at rest. This means the displacement \( d \) of the toolbox is zero, as it does not move while the worker applies force.
03

Apply the work formula

Substitute the displacement \( d = 0 \) into the work formula: \( W = F \cdot 0 \cdot \cos(\theta) = 0 \). Since the displacement is zero, the work done by the worker is also zero, regardless of the magnitude of the force applied.

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Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Physics Concepts
In physics, the idea of work and energy is fundamental to understanding how objects move and interact. When we talk about **work**, we refer to the scenario where a force causes an object to move or change its position. However, work isn't just about moving things; it involves the direction and the component of the force involved as well.

The formula for calculating work is generally expressed as \( W = F \cdot d \cdot \cos(\theta) \). Here, each element has a specific role:
  • \( W \) stands for work, typically measured in joules (J).
  • \( F \) represents force, measured in newtons (N).
  • \( d \) indicates displacement, in meters (m).
  • \( \cos(\theta) \) accounts for the angle between the force and the direction of the displacement.
For work to occur, the point of application of the force must move in the direction of the force applied. If there is no movement, as in the case of the toolbox remaining still, then technically, no work is done from a physics standpoint.
Force and Displacement
Force and displacement are two key components when discussing work. Let's look deeper into what they mean individually and together.

**Force:** A force is any interaction that, when unopposed, changes the motion of an object. This is measured in newtons (N), and could be a push or pull. In the scenario where a worker pushes a toolbox on a ramp, the force is applied in the form of a push.

**Displacement:** Displacement refers to the change in position of an object. It's a vector quantity, meaning it has both magnitude and direction. If the object doesn't change its position, its displacement is zero.

For work to be done, the object must move in the same direction as the applied force. Going back to our original problem, even though a force is applied to the toolbox, since it does not move, the displacement is zero and therefore no work is done.
Calculating Work
To calculate work, several variables need to be considered, as shown in the formula \( W = F \cdot d \cdot \cos(\theta) \). Let’s break down how to use this formula effectively:

**Step-by-step Calculation:**
  • Identify the **force (F)** being applied. This is usually given in the problem statement.
  • Determine the **displacement (d)** of the object. Here, measure how much the object moves in the direction of the force applied.
  • Find the angle **(\(\theta\))** between the direction of the force and the direction of displacement. If they are in the same direction, \(\theta = 0\), making \(\cos(\theta) = 1\).
  • Substitute these values into the formula to find the work done.
In the case of our factory worker, since the displacement is zero, the computation simplifies as the work done is zero. Understanding how to apply these steps is crucial since they show why no work is done when there is no displacement, even if force is applied.

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